ABS (Antilock Brake System)

BRAKE CONTROL: ANTI-LOCK BRAKE SYSTEM: C0278/11: Open in ABS Solenoid Relay Circuit

DTC C0278/11 - Open in ABS Solenoid Relay Circuit

DESCRIPTION

This solenoid relay supplies power to each ABS solenoid. If the ABS initial check is OK after the ignition switch is turned on (IG), the skid control ECU will turn the ABS solenoid relay on.
HINT: (Initial Check)
If a speed signal of 4 mph (6km/h) or more is input to the skid control ECU, with the ignition switch on and the stop light switch off, the ECU performs self diagnosis of the motor and solenoid circuits.





WIRING DIAGRAM





INSPECTION PROCEDURE
HINT: When C1241/41 is output together with C0278/11, inspect and repair the trouble areas indicated by C1241/41.

PROCEDURE

1. INSPECT FUSE (ABS/VSC No.2 FUSE)





(a) Remove the ABS/VSC No.2 fuse from the engine room R/B.
(b) Measure the resistance according to the value(s) in the table below.
Resistance:






NG -- INSPECT FOR SHORT IN ALL COMPONENTS CONNECTED TO FUSE AND REPAIR OR REPLACE THEM IF NEEDED, AND REPLACE FUSE
OK -- Continue to next step.
2. INSPECT SKID CONTROL ECU CONNECTOR (+BS TERMINAL VOLTAGE)





(a) Disconnect the skid control ECU connector.
(b) Measure the voltage according to the value(s) in the table below.
Voltage:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (+BS CIRCUIT)
OK -- Continue to next step.
3. INSPECT SKID CONTROL ECU CONNECTOR (GND TERMINAL CONTINUITY)





(a) Disconnect the skid control ECU connector.
(b) Measure the resistance according to the value(s) in the table below.
Resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (GND1 CIRCUIT)
OK -- Continue to next step.
4. RECONFIRM DTC
HINT: This codes is detected when a problem is identified in the brake actuator assembly.
The solenoid circuit is in the brake actuator assembly.
Therefore, solenoid circuit inspection and solenoid unit inspection cannot be performed. Be sure to check if the DTC code is output before replacing the brake actuator assembly.
(a) Clear the DTC.
(b) Start the engine.
(c) Drive the vehicle at the speed of 12 mph (20 km/h) or more for 30 seconds or more.
(d) Check that the same DTC is recorded.
Result:





HINT:
- If the normal system code is output (the malfunction code is not output), slightly jiggle the connectors, wire harnesses, and fuses of the brake actuator assembly. Make sure that no DTCs are output.
- If any DTCs are output while jiggling a connector or wire harness of the brake actuator (skid control ECU), inspect and repair the connector or wire harness.
- These DTCs may be stored due to a malfunction in the connector terminal connection, etc.

B -- REPLACE BRAKE ACTUATOR ASSEMBLY
A -- END